Like a fingerprint, every computer has a set of parameters which make it possible to create a unique ID. California based BlueCava has catalogued 200 million devices so far, and hopes to have a billion by the end of next year.

Unlike cookies, which users can delete or prevent from being shared, it is extremely difficult to disguise the identity of a device from these kinds of fingerprinting techniques.

The Journal couldn’t resist dipping into the quirky history of this fingerprinting technique. “BlueCava’s secret sauce hails from Sydney, Australia, in the early 1990s. Back then, inventor Ric Richardson was helping musicians including the band INXS to use new software for playing their electronic keyboards.”

Richardson wanted to let customers test out his software without giving them the ability to pirate copies for friends. So he developed a way to identify computers based on hundreds of individual properties like fonts, screen size and clock settings. Only authorized machines could run his software.

Once a machine is IDed, BlueCava matches that data with offline records from companies that collect voter rolls and DMV info. The complete profile can be extremely detailed.

“I think cookies are a joke,” BlueCava CEO David Norris told The Journal. “The system is archaic and was invented by accident. We’ve outgrown it, and it’s time for the next thing.”